I get patterns at all the above, too. I pay for some, get some free and get some books. I have the custom knits book, too and I really like it!
I like to be able to really look at pattern construction before I buy b/c I hate seaming! I try to stick with one piece patterns or patterns that can be adapted to one piece. Therefore, I don't buy too many patterns on line b/c they don't always say the type construction.